Signs and Symptoms of an Infection After Surgery

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If you are recovering from surgery, it is important to take the right steps to prevent infection. Infections after surgical procedures can affect the incision, bladder, lungs, intestines, or bloodstream.

Doing all the right things after surgery can lower your risk of an infection, but it doesn’t completely guarantee that you will be infection-free.

This article discusses infections after surgery and how to prevent them. It also looks at types of infections, symptoms, and when you should see a doctor.

Post-Surgery Signs of Infection

Verywell / Joshua Seong

Types of Infections

Infections of the incision and urinary tract infections (UTIs) are among the most common types of post-operative infections. Having a urinary catheter (a tube inserted into the bladder to drain urine) during or after surgery increases the chances of a UTI.

Pneumonia, a serious lung infection, can also develop after surgery.

Taking antibiotics to treat or prevent infections can increase the risk of infection from Clostridioides difficile (C. diff), a type of bacteria in the digestive tract.

And less commonly, a serious bloodstream infection, septicemia can develop, sometimes leading to sepsis, a dangerous inflammatory response to the infection.

Symptoms of Infection

It is important to watch out for symptoms of infection. If you notice any of these symptoms after surgery, call your doctor.

Infected Surgical Incision Symptoms

Be aware of these signs of infection:

  • Hot incision: An infected incision may feel warm or hot to the touch. This happens as the body sends infection-fighting blood cells to the site.
  • Swelling/hardening of the incision: An infected incision may harden. This happens as the tissue underneath becomes inflamed. The incision may also look swollen or puffy.
  • Redness: Some redness at the incision site is normal. The red color should decrease over time. If it becomes redder, it may be infected. Red streaks radiating from the incision to the surrounding skin are a sign that infection is spreading.
  • Drainage from the incision: An infected incision may produce foul-smelling drainage or pus. The pus can be blood-tinged, green, white, or yellow. The drainage may also be thick.
  • Pain: You should have a slow and steady improvement of your pain as you heal. It is normal to have a mild to moderate increase in pain after activity. You may also notice more pain if you take less pain medication. If pain at the surgery site increases and you don't know the reason, you may be developing an infection. Tell your surgeon about any significant, unexplained increase in pain.

You can help prevent infection by taking care of your incision.


An infected incision may be red or swollen. It may feel warm, painful, or drain pus.

Urinary Tract Infection Symptoms

Urinary tract infections are not uncommon after surgery. This can occur when you don't drink enough fluids and when you don't urinate frequently enough. Bacteria can build up in the bladder, leading to a UTI.

Urinary catheters can sometimes become contaminated, or your bladder muscles might weaken after you've had a urinary catheter in place for several days or longer.

Symptoms of a UTI include:

  • Burning with urination
  • Urgency, or a sudden, immediate need to use the bathroom
  • Needing to urinate frequently
  • Lower abdominal pain

Pneumonia Symptoms

People recovering from surgery are at risk of developing pneumonia. This is usually a result of decreased mobility and decreased coughing.

Symptoms of pneumonia can include:

  • Fatigue
  • Fever
  • Cough
  • Trouble breathing
  • Wheezing breath sounds
  • Decreased appetite

C. Diff Symptoms

The antibiotics you receive during surgery can put you at risk for C. diff infection. This is a bacterial infection of the large intestine.

Symptoms include:


Watch for signs of other types of infections besides incisional infections, including burning or urgent urination, a cough, and severe diarrhea.

Systemic Infection Symptoms

A systemic infection is an infection that spreads through your body, and it can be serious. Common symptoms are fever and malaise.

Malaise is when you feel tired and lack energy. You may sleep more than usual. You may not feel up to doing normal things. These feelings are common after surgery.

The timing can help distinguish normal post-operative symptoms from an infection:

  • When recovering from surgery, most people feel a bit better each day.
  • Someone developing an infection may feel better for a few days, then suddenly feel exhausted and lethargic.

A fever, chills, and a diminished appetite can also occur with systemic infections.

It is common to have a low-grade fever low-grade fever of 100.4 F or less in the days after surgery. Tell your surgeon if you have a fever above 100.4 F.

Septicemia and sepsis can cause chills, changes in blood pressure and heart rate, difficulty breathing, and decreased consciousness—and may be life-threatening.


Systemic infection can be serious. Call your doctor if you develop malaise or a high fever.

Watch for Signs of Infection

You can check for early signs of infection so you can get prompt medical attention to prevent it from getting worse.

Things you can do:

  • In the first few weeks after surgery, inspect your incision every day for signs of infection.
  • You should take your temperature daily. This can help you identify an infection early. It is best to take your temperature at the same time each day.

It is important to identify an infection right away. Prompt care can keep it from becoming more serious.

If you are diagnosed with an infection, your surgeon can prescribe antibiotics to help it resolve and to prevent it from spreading.

When to See a Doctor

See a doctor if you think you might have an infection of any kind. Any infection after surgery can become serious. Life-threatening complications can start with a small area of infection.

For example, a UTI can lead to sepsis, which can cause septic shock. Septic shock causes decreased blood pressure and can lead to organ failure. Treatment of septic shock requires intensive care.


Even if you are careful, an infection can happen after surgery. You may develop an infection in your incision. You could also develop a UTI, pneumonia, or another type of infection.

Watch for redness, swelling, drainage, pain, and warmth at the incision site. If you have a UTI, you may have a burning sensation with urination or a sudden or frequent need to urinate.

Systemic infections can become serious. Symptoms include fever and malaise.

Infections can become life-threatening. Call your doctor if you notice any symptoms of infection.

A Word From Verywell

Infection is a risk after surgery. It is worth the effort to prevent infection when you can. Infection delays healing and can lead to scarring. An infection may cause pain and prolong recovery time. In the most severe cases, hospitalization or intensive care are needed.

The good news is, you can do simple things to prevent infection. Recovery from surgery can require your effort and attention—especially after major surgery. Make sure you follow your post-operative recovery instructions so you can heal faster, with a lower chance of complications.

Frequently Asked Questions

  • What is the risk of developing a surgical site infection?

    Between 2 percent and 5 percent of patients who undergo surgery develop a surgical site infection (SSI).

  • How quickly can an infection develop after surgery?

    Surgical site infections usually develop within 30 days. However, with surgeries to place some sort of implant, an infection may occur within 90 days.

  • What are the different kinds of surgical site infections?

    There are three types of surgical site infections (SSIs):

    • Superficial incisional: Limited to the incision area
    • Deep incisional: Occurs under the incision and affects muscle and surrounding tissue
    • Organ or space: Involves any other area of the body, including an organ or space between organs
  • How common is pneumonia after surgery?

    Pneumonia is the third most common infection associated with surgery. In studies, the incidence of pneumonia developing within 48 to 72 hours of entering the hospital for surgery has ranged from 2.7 percent to nearly 29 percent.

13 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Tambyah PA, Oon J. Catheter-associated urinary tract infection. Curr Opin Infect Dis. 2012;25(4):365-70. doi:10.1080/13697137.2021.1948995

  2. Abdelsattar ZM, Krapohl G, Alrahmani L, et al. Postoperative burden of hospital-acquired Clostridium difficile infection. Infect Control Hosp Epidemiol. 2015;36(1):40-6. doi:10.1017/ice.2014.8

  3. MedlinePlus. Surgical wound infection – treatment.

  4. Stevens DL, Bisno AL, Chambers HF, et al. Practice guidelines for the diagnosis and management of skin and soft tissue infections: 2014 update by the Infectious Diseases Society of America. Clin Infect Dis. 2014;59(2):e10-52. doi:10.1093/cid/ciu444

  5. Alexander-Magalee MA. Recognizing surgical site infections. OR Nurse.

  6. Centers for Disease Control and Prevention. What is C. diff?

  7. Chahoud J, Kanafani Z, Kanj SS. Surgical site infections following spine surgery: eliminating the controversies in the diagnosis. Front Med. 2014;1:7. doi:10.3389/fmed.2014.00007

  8. Narayan M, Medinilla SP. Fever in the postoperative patient. Emerg Med Clin. 2013;31(4):1045-58. doi:10.1016/j.emc.2013.07.011

  9. Hsiao CY, Yang HY, Chang CH, et al. Risk factors for development of septic shock in patients with urinary tract infection. Biomed Res Int. 2015;2015:717094. doi:10.1155/2015/717094

  10. Mathur P. Hand hygiene: back to the basics of infection control. Indian J Med Res. 2011;134(5):611-20. doi:10.4103/0971-5916.90985

  11. Sikora A, Zahra F. Nosocomial Infections. In: StatPearls [Internet]. Treasure Island, Fla: StatPearls Publishing

  12. Johns Hopkins Health. Surgical site infections.

  13. Chughtai M, Gwam CU, Mohamed N, et al. The epidemiology and risk factors for postoperative pneumonia. J Clin Med Res. 2017;9(6):466-475. doi:10.14740/jocmr3002w

Additional Reading

By Jennifer Whitlock, RN, MSN, FN
Jennifer Whitlock, RN, MSN, FNP-C, is a board-certified family nurse practitioner. She has experience in primary care and hospital medicine.